The Shrimp Cycle: Removal timing & first livestock

[Dego Red]

This isn't something I thought about until now. My diatoms are in full swing with exponential growth in both color and surface area. Eventually they're gonna peak, die off, and my cycle should be nearing end. This is week 5 already. Shrimp #1 is gone, #2 about 1/2 decomposed. This brings a couple questions -

Should I pull the shrimp when my ammonia levels zero out? I'd hate to keep the shrimp in there producing ammonia to feed additional bacteria that will starve when it's gone, producing a mini-cycle.

Should I stock right after the shrimp comes out/completely dissolves? After a 50% WC, I'd hope to have A/N/N at 0/0/<10. If the water is acceptable, wouldn't the introduction of coral or a fish blend in closely, continuing to feed the N/N bacteria without die off?

When I do decide to stock, where should I start outside of a CUC? I know corals produce less waste for a slow increase in bioload/bacteria production, but they generally require better water conditions that a very new tank may not have. Fish, on the other hand, can tolerate *slightly* more unstable conditions (NO3, etc), but also produce more waste and I don't want to shock the system, killing the fish.

I'd eventually like to have one or two clowns, maybe one or two other rather small fish, a shrimp (cleaner or blood), definitely an anemone, zoas, and then SPS down the road. I'd like to start with the anemone first, then clowns, and so on, but I'm almost certain the water conditions won't be suitable for it near the beginning.

Specs:
Three-sided 30g, alternating modded MJ400's via AC Jr, Tunze 9002 skimmer, 150w MH, 20# Marco dry rock, 20# live sand.

[Kevin1000]

Pull the shrimp out - once you have a bit of ammonia the cycle starts .. additional ammonia just creates more bacteria which then starves and creates more ammonia etc .. called overshooting.

FYI .. next time around - while use of shrimp is popular .. if you have live rock its not necessary. Further a small amt of pure unscented ammonia serves the same purpose and is arguably better.

Hope this helps.

[Dego Red]

Ok, I'll pull it tonight. But keep in mind I only started with it since my rock was dry and needed some way to introduce ammonia at a sustainable level similar to that of what a light bioload would produce. I do suppose the first shrimp may have accomplished that, but I'll have at least two more weeks to level out my A/N/N while the diatoms run their course.

Any thoughts on introduction timing for a CUC an at least one fish? I'm guessing within two days of leveling ammonia/nitrite and a WC to drop nitrate to prevent die off of beneficial bacteria...but this is were experience comes into play. I don't want to wait 6-7 weeks just to create a secondary cycle...

[Kevin1000]

Most would recommend holding off CUC until tank has finished cycling. While the tank is cycling you should consider setting up a QT which is almost mandatory in SW ... takes about 4 weeks to QT fish so the fish should be ready about the time your tank has cycled.

[Dego Red]

Of course. When I said within two days, I meant after the cycle has finished. Some have said "they'll be OK", but that's not not what I'm doing this for. I'll be waiting.